(5) Talk about connectors and the guy says he doesn't own 'a soldering iron'.

I was chatting with Don Allen, W9CW, a few weeks ago. He's retiring as ad sales agent for CQ. I mentioned to him about my survey showing the decline in number of equations and schematics in QST, CQ, Monitoring Times, etc. Guess that FACT is a sign of the times. In some ways, perhaps, hams have gravitated to "social media" behaviors/interests.

There were still chunks of good "techy" content in the mags up through the 1980s - pre-internet. Take for example, N4UU's article "Optimizing Coaxial-Cable Traps," found in December 1984 QST. It not only had six equations but even a calculus solution for a "minimal" in coax length for best trap AND graphs! This article, by the way, is the solution source for some of the trap calculators you find on the web now such as "Coaxial Trap Design." N4UU even applied for and received several patents!!!: 4,335,386 for one. 73, Phil, W0XI.

There is nothing wrong with SRP and I don't think you meant there was. It's just that the interests of hams have changed for the most part. Maybe it was the "tuned out" flower children of that last generation that didn't peddle techy to their kids that caused this shift? And yet, if we look carefully, there is still a small batch of techs out there. Maybe we're remembering our past too fondly; perhaps the "techies" were always a small % of the total? 73, Phil, W0XI.

I do believe they are 'spark-gap' transmitters. Nevertheless, did you hear it on the air? Just curious, because 1) I'd like to hear one actually transmitting and, 2) I bet the FCC wouldn't want to hear one.

I built a low-level spark transmitter last year in order to determine the level of ultrasound produced by a spark bridging a small air gap. You'll find my article, "Ultrasound Pressure of a Weak Spark" in the July 2010 issue of the Xtal Set Society Newsletter re www.midnightscience.com. Or download the pdf here:

Friedrich Paschen (in 1989) measured the voltage required to bridge the gap for various spacings and create a spark. The formula is called Paschen's Law. At 0.02 inches the minimum voltage at 1 atmosphere is 327. Why the research? It turns out that detecting 40 kHz ultrasound, using an audio dish and receiver. enables one to locate which power pole and where on a specific pole that spesky RF interference in your 20 or 40 meter receiver is coming from!

Nevertheless, did you hear it on the air? Just curious, because 1) I'd like to hear one actually transmitting and, 2) I bet the FCC wouldn't want to hear one.

Never heard one on the air, but have seen spark in action up-close and personal (into a dummy load). Amazing. The flash is blinding, the roar is deafening, and the ozone aroma is not to be forgotten.

The set in the youtube video runs a kilowatt input - the old US amateur maximum power. By commercial standards, however, it wasn't all that big; ships routinely carried 5 and 10 kW sets of similar design for 600 meters.

Spark was officially banned from amateur radio in the late 1920s, but by then hams had simply stopped using it. The newfangled tube transmitters gave better results at lower cost, and on the short-waves the advantages of tube transmitters were even greater than on 200 meters. (Note that when Godley went to Ardrossan for the 1921 Transatlantic Tests, he heard more tube than spark rigs even though the tube sets were generally running lower power and were less numerous).

Btw, spark remained legal into the 1960s in the maritime service. All ships above a certain size were required to have radio, of course, but they were also required to have a backup-set capable of operation on 600 meters. The treaty and FCC allowed the use of spark sets for backup on some older ships well into the 1960s (1966 was the cutoff date IIRC).

It's just that the interests of hams have changed for the most part. Maybe it was the "tuned out" flower children of that last generation that didn't peddle techy to their kids that caused this shift?

I don't think so.

I think that ham radio has never really been all that popular/mainstream, if you look at the USA as a whole. If you figure out how many US hams there were as a percentage of the population, we're at or near the peak right now. Decades ago, we made up a much smaller fraction.

For example, I graduated from high school in 1972. I went to an all-boys school in suburban Philadelphia, (Monsignor Bonner HS).

When I went there, at the peak of the baby boom, there were about 2500 students in the school, and at least that many in the girls' high school next door. Yet out of those ~5000 middle-class suburban kids, there were never more than a handful of licensed amateurs. The peak was less than 10 - fewer than 1 in 500.

This was before the internet, cell phones, PCs, etc. It was before CC&Rs and HOAs were common, when Heath and other kits were all over the place, and when every town of any size had a real radio-parts store. (We had several within a few miles, plus Philly's version of "radio row" down on Arch Street).

I'm thinking about attaching a snug fit base speaker to my toilet bowl (throne) next halloween and sending near subliminal dots and dashes - let's say at 30 to 60 Hz - to see if my neighbor can hear them at his throne, hi. Think I'll send CQ DX. I'm going to call this sludge-net. No "digit" repeaters allowed. Sparks here will not be welcomed! They could be dangerous, hi. 73, Phil, W0XI. It's true; I actually intend to try this for fun.

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